Characterization of tumour and non-tumour primary cultures. A. Organoid-derived cultures (A, top panels, 10X magnification) from both tumour and non-tumour specimens had large polygonal cells (lower panels, lpc) surrounded by small polygonal cells (lower panels, spc, 20X magnification). B. Representative tumour and non-tumour cultures (passages 1-3) were analyzed for expression of the epithelial markers K19, K18 and ESA and the myoepithelial markers SMA, K14 and vimentin (scale bar 50 μm). C. Representative cultures were immunoblotted for expression of epithelial (K19, K18) and myoepithelial (vimentin, p63) markers.